Electric burglar alarm for motor vehicles



Aug., 30, 1927. K i 1,640,603 L.HADDow ELECTRIC BURGLAR ALARM FOR MOTORVEHICLES y Filed Deo. 12. 1925 7l l Patented Aug. 30, 1927.

UETED. STA

LAURENCE HADDOW, or COLMQR, NEWy MEXICO.

ELECTRIC BURG-LAR ALARMijFOR MOTOR-VEHICES. l l

Appiication inea December This invention relatesto improvements inburglar alarm systems and'is more particularly adapted for use uponmotor vehicles.l @ne of the important objects of the presbeing further;of sucha` nature toattract attention so that. the, samey will be` caused1 to be operated whereupon the signal willi be automatically soundedshould any one atr tempt V'to operate the aforementionedy means withoutknowing the proper, combination provided for preventing, the. closing ofthe circuit to the signal.

A still-further obj ect; is to provide aswitch. for electric burglaralarm systems on motor.- vehicles which will; at. all times be positiveand eiiicient in carrying out the purposes for whiclrit is designed,thesame being of. such construction as to kobviatethe necessity ofhaving to employ a means for-.actuating the same. y

il. stillifurther. obj ect is to provide aswitch ofthe above characterwhich issirnplein construction, inexpensive, strong andV duf rableandfurther well. adapted tothe purpose for which-it isdesigned. 4

Other obl'ects and advantages offtheinv vention will become,- apparentduringthel course of the. following description taken in connection withthe accompanying. draw.- ing. l i

1n the accompanying drawing forming part of this application and inwhichlile numerals designate like parts throughout the same: l

Figure 1` is a wiring` diagram illustrating the ignition system andshowing` the manner in which my improved switch is associated therewithandwith the audiblesignal.

Figurev 2 is vertical sectional view through the housing or casingsecuredl on the front or inner face `ofthe dash board of a motor vehicleanddisclosing the man-y ner in which the switch is arranged on the dashboard.

Figure 3 is a 'view partly. in elevation 12, 1925. serial N9. 75,065.

and4 partly in section of ay switch, the view being'a top plan. V

Figure tis a front elevation of the switch, and Y Figure is a. rearelevation.

Inl the drawing wherein .for they purpose ofillustration is shown thepreferred embodimentof. myv invention, theVV numerals 1A and 2 designatethe frontfandrearbase plates respectively, the same lbeing o frectangular design and being adapted tothe.. secured yon the oppositesides ofv the dashboard 3 of a motor vehicle through the medium of thefastening elements 4; which extendgthrough the openings 5 providedtherefol` inthe respect-ive corners of each of the plates,

Carried by the rear plate@ is a, contact plate designated'generallybythe muneral 6, thesame including the substantially circular endyportions 7 and 8 respectively, the same being connected together.through the medium of the reduced intermediate portion 9. 'lhisvconstruction ismore. clearly illustrated in Figure 5 of thedrawino'.` 1Asleeve 10 of. knon-,conductive material extends centrally through each.of the Acircular portions of the contact plate 6, the` forward portionsof the sleeve extending through the front andrear base plates as wellasthroughthecdash board. 3,y A pairVV of` dials 11v and' 12 respectivelyare secured on the forwardendsof the non-conductive sleeves 10` whichextend, through the contact portions 7' and 8 respectively, andthesedials are disposed adjacent the front base plate 1 Each ofthedials isprovided with .suitable vindicia such asis shown at 13, and

the. purpose of these dials will. hereinafter'y be more Afullydescribed.

A fiat arm. 14 also, of a non-conductive material is yprovided at itsinner end with an eye which is ittedover the inner end of each ofthe:insulated sleeves 11, and. is securedrthereon by means of the set screw14. Each arm extendsradially from the insulated sleeve against theouter.face of the contactplate 6, as. is clearly illustrated in Figures Sand 5of the drawing. Thekouter end. ofv each. of the insulatedv arms. 14terminata fluslrwith the peripheral edge of therespectivetcircularend'portions ofthe contact plate Gasisalso clearly illustrated inFigures 3 and 5.

Extending longitudinallythrough each of the insulated sleevesandjadapted for rotation thereinis the spindle 15. The spindle p therotation thereof.` A pointer .17 in the form of a rib is formed on theperipheral 'edge of each of the knurledknobs and is adapted forcooperation with the indicia on the respective dials 11 and 12 in themannerl clearly illustrated Vin Figure 1.

A contact arm or finger 18, and formed of a strip of spring metal,issecured at its inner end on the inner end of eacii spindle 15 and as islmore clearly illustrated in Fig-V ure 3, each of the contact arms orfingers is curved or bent anguiarly and the tapered outer end of thesecontact arms is rounded so as to be free to pass over the respectiveinsulated pieces 14. I

Each spindle is preferably in the iorm oit a bolt, and the innerthreadedend thereof provides a terminal or binding post. Suitableclamping nuts 19 are associated with the inner headed end of each boltas is clearly shown in Figure 3. Y

@ne of the wires from the ignition circuit which extends or connects thespark plugs with the magneto is tapped as indicated by the wire shown at20, andthis wire 2O is secured to the terminal or inner end of thespindle which extends through the circular portion 8 of the contactplate 6.

rlhe spark plugs are illustrated at 21, and the wiring between the plugsand the magneto 22 is illustrated at 23. v

Tie other terminals or inner end of the other spindle is connected tothe audible' signal 24 which is preferably a horn or siren by the wire25 and the horn isrvalso arranged in a suitable electric circuit, thesource of energy'therefor being shown at 26.

The portion of the switch which is arranged on the side of the dashboard below the hood is enclosed within a suitable housing or casingshown at 27. The siren or horn 24 which forms the audible signal in thepresent invention is also arranged Within this housing and furthermorethe wires 23 which lead from'the spark plugs of the internal combustionengine (not shown) to the magneto `also extend through the housing tosuitable openings provided therefor, such as is shown at 28,. Access tothe parts of the hinge enclosed within the .housing is had through themedium of ahinged door 29, and normally the latter is held in a closedpositionby a suitable padlock or the like, shown at 30. Openings 31 areformed in the door 29 whereby the sound from the audible signal may beemitted so as to enable the signalvto be easily heard.

lVhen the insulated strips 14C are disposed in any predeterminedposition against the rear plate 2, and the spring contactl fingers orarms 18 have their outer ends resting on theinsulated members 14:, inthe 'manner show-n vin Figure 3, the circuit to the signal Ais broken,and the sounding of the alarm Should any unauthorized tated-so that thespring Contact fingers areY moved out of engagement with the Vinsulatedstrips la and are brought into engagement with the circular portions 7and 8 of the con act plate 6, the circuit tothe audible signal will beclosed andA immediately the siren will be operated and will continue toYoperate, thereby operating a warning to indicate that. the vehicle isbeing driven by an unauthorized person.`

kIt is of course understood that the Vproper person knows the positionat which the knobs should be set so as to position the spring contactfingers over the insulated strips 111 and the pointer 17 will cooperatewith the indicia 13 on the respective dials to enable ai person toreadily ascertain the position of the spring contact fingers carried lonthe inner ends of the spindles. It is obvious that when the insulatedarms 14k are moved, another combination must be used in order to preventvthe spring contact fingers engaging the contact plate, and actuatingthe signal when it is not desired to do so.V Y

'A circular series of notches 32 are arductive arm 14. This ratchetdevice will i hold the arms la in any adjusted position againstaccidental movement. By rounding the outer end of each of the springcontact fingers, the latter will be permitted to freely move over therespective insulated strips.

Anelecrtric burglar alarm of the above mentioned character may bereadily and easily attached on a motor vehicle instrument or dash boardwithout necessitating any material alterations,and furthermore the alarmmay be easily connected with the ignition system. The simplicity inwhich Vmy" improved switch is constructed renders the same positive andefcient in its operation at all times, and byenclosing the parts in asuitable casing or housing which is con-V cealed beneath the hood, therewill bene possibility of the burglartamperingV with the parts of theswitch which affect the actuation ot the audible signal.

In the event that the authorized person should forget to turn the switchon when he leaves the vehicle, and should any unauthorized person enterthe vehicle and attempt to steal the same, the'attention of such personwill be attracted by the alarm device and as a result will attempt toactuatethe dials and knobs thinking that the same has some connectionwith the ignition system and effects the starting of the vehicle. Suchoperation of the device on the part of an unauthorized person will setthe alarm. i v

lllhile l have shown the preferred embodiment of my invention it is tobe understood that minor changes in the size, shape and arrangement ofparts may be resorted to without departing from the spirit of theinvention and the scope Vof the appended claim.

Having thus described the invent-ion, what l claim as new is A switchcomprising a pair of plates adapted to be secured on opposite `sides ofan automobile dashboard, a contact plate supported on one ofthevaforementioned plates, a sleeve of non-conductive material extendingthrough the dashboard andy through the first mentioned pair of plates,Vand also l through the contact plate, a strip of non-conductivematerial secured on the inner end of the sleeve and adapted to cover aportion of the contact plate, said Contact plate being provided with aseries of spaced annular depressions in the outer face thereof, aprojection formed on the bottom face of the insulated strip adapted forcooperation with said depression for holding the strip in any adjustedposition, a dial member secured on the outer end of the sleeve andadapted for rotation therewith, a rotatable spindle eX- tendinglongitudinally through the sleeve, a spring Contact linger carried bythe inner end of the spindle and normally adapted to rest on theinsulated strip, and a knob on the outer end of the spindle foractuating the same whereby the spring contact finger may be moved out ofengagement with the insulated strip and into engagement with the contactplate, and a pointer element carried by the knob and cooperating withthe dial for indica-ting the positions of they spindle and the springContact finger carried thereby.

In testimony whereof I aiiiX my signature.

LAURENCE HADDOV.

